So, no matter how bright the light, if it's going through an atmosphere with particles in the air, eventually, there will be too many particles for the light to shine through.

I'm not talking about it traveling to the end of the earth (Ha!), just sufficiently beyond the horizon to demonstrate there is no curve. The distance of the horizon in kilometers = 3.569 times the square root of the antenna height in meters.

Look at how you believe these things you've read without any proof.

The real reason you can't do it is because nobody can do it because the earth is round.